I'm often surprised by how much blood, gore and violence is in a PG-13 film (but then, the MPAA is much more fainthearted when it comes to sexuality than they are with violence - but don't even get me started on that). However, 13 - 17-year-olds can still see an R film - they just have to be accompanied by someone who's 18 or older - not something that was ever very hard to arrange when I was 13 - 17.